Various cartons have been provided for containing products such as frozen pizza pie. For the most part, these cartons comprise a disc of paper board on which the frozen pizza pie is positioned, and the product is over wrapped with a plastic film which is marginally secured to the underside of the disc. Under normal circumstances, the circular pizza is removed from the package, and rested upon a flat sheet in an oven while in its frozen state. It has now been proposed to cut the circular pizza pie into wedge shaped segments and to insert these segments into a generally triangularly shaped carton which may be heated in a very short period of time in a microwave oven or the like. Such ovens are readily available, and are often used in places of business to heat frozen sandwiches and the like.
One of the problems involved lies in the fact that the carton containing the product must be vented so that the moisture vapor escaping from the product during the heating process can escape. At the same time, however, the product must be sealed within the carton during storage and shipment to prevent it from becoming contaminated.